An Eye For An Eye
by Lt. Lysander
Summary: A life of peace is all they've ever known, so what happens when it's taken from them? As they embark on a quest to bring back their loved ones, they find themselves face-to-face with old friends and enemies alike, but who is the true mastermind behind all this?
1. Prologue

**A/N: This is gonna be my main focus for the next few months, depending on how long I plan to drag this out. If I'm lucky, this'll be a piece of cake. If not, then we'll see. So, I hope you guys enjoy this.**

* * *

You must be new around here. How's about a quick history lesson?

Keyblades have been around for as long as I can remember. From the time of the Keyblade War, and honestly, it's called that for a reason, to the time of Sora. They've probably always been around, just that we humans were a little slow on mastering the art of wielding them.

I don't know for sure, and I probably never will. Not that it bothers me. What bothers me is what some people do with their Keyblades. They think they can control the hearts of everyone around them and use that to their advantage.

That's where they're wrong. If their heart isn't strong enough, they won't even be able to wield the Keyblade anymore, let alone control others' hearts.

But hey, that's not what we're here to talk about, so let's move along. In the beginning, there was the Keyblade War. Now, that happened because people decided they wanted Kingdom Hearts all for themselves. End result: no one got it, and pretty much everyone died. The survivors learned their lesson, and when the World was restored, they decided they'd take better care of it this time.

Of course, there were still people who wanted Kingdom Hearts. Keyblade wielder or not, we're all human. I suppose you could say desire is our basic nature. Anyhow, there's this guy called Xehanort. Why he wanted Kingdom Hearts is still a mystery to me, but I know this much: he was insane. Not complete psycho kind of insane, just that his ideas were always a little bit nutty.

So, he wanted Kingdom Hearts, and to get it, he needed the χ-blade. Now, this isn't your average Keyblade. This χ-blade is a one-way ticket to Kingdom Hearts. Sounds pretty powerful, doesn't it? The problem is in creating it. You need to have two hearts, one of pure light and one of pure darkness, fight each other. And that's exactly what Xehanort did. Not that it worked, though, seeing as the legendary trio, Terra, Ventus and Aqua put a stop to it.

Years go by, and we see Sora, Riku and Kairi take on Xehanort's Heartless and Nobody. In case you didn't know, Heartless spawn when darkness takes over one's heart. That's why we have to protect ourselves. Nobodies, on the other hand, come from what's left over after we become Heartless—the body and the soul, if they're strong enough, turn into Nobodies. Now, when you kill the Heartless and the Nobody of the same person, they come back to life. Guess what happened to Xehanort? Yeah, he came back.

Long story short, Xehanort was revived, but King Mickey, Sora, Riku, Kairi, Lea, Aqua and Ventus took him down together. And then Terra came back. That was two hundred years ago.

Are you up to speed now?


	2. Chapter 1: The Islands

"Wear the face of despair!"

The cloaked man laughed as his weapons returned to him. He threw them above his head, and leapt after them. One by one, they formed a chain, with the man at its helm. The spears, now shaped like a serpent, flew overhead before heading under the bridge. It reappeared on the other side, the cloaked man smirking as the head of his spear-serpent split into three. A tornado formed at the serpent's mouth as it swerved to the right side of the bridge.

The man smirked again as he locked on to his target: a young boy, about fifteen, with blonde hair and blue eyes. Unique, yes, but hardly what set him apart from most of the other boys and girls his age. No, his most distinguishing feature was the weapon he wielded in his right hand; the Keyblade.

_I only have one shot, _the boy thought as his eyes locked with that of his opponent. He moved backwards, pushing himself up against the edge of the stone bridge. Glancing to his left, he noticed the serpent was about ready to strike.

He charged, and in that same instant, the serpent attacked, releasing its hurricane across the bridge. It was a strong move, and one with great range, at that. But the boy was prepared. As the winds drew closer, he jumped, narrowly avoiding the attack as it swept across the bridge. He glanced to his right this time, and, noticing the approaching serpent head, quickly used his momentum while airborne to spin himself. Slowly, at first, then, gradually, he picked up speed. He felt the winds roll over him harmlessly as he passed through the tornado. His eyes trained on his target, he swung his blade.

The man cried out as the blade stabbed through him, and a bright light shone from his chest. The boy closed his eyes as he landed, the light enveloping the entire bridge. When he opened his eyes once more, his foe was nowhere to be seen. All that remained was the battleground and a single item, floating where his opponent once stood.

The boy smiled. Grabbing the item, he turned and walked towards the blue portal behind him. He squinted as he exited the portal, his eyes not used to the sudden increase in brightness. He inhaled, the waters of the Rising Falls splashing behind him. Looking around, he saw a few other Keyblade wielders in the Garden of Assemblage.

_Probably waiting for their friends, _he thought. He glanced at his newly-obtained item. _A Defense Boost, huh? _He tossed it into the air, and watched as it shattered, its energies forming a yellow-tinted sphere around him. As he absorbed the sphere, he felt different. And to an extent, stronger.

"I see you've already used the drop, Len." The blonde felt a hand pat him on the back. He turned and, upon seeing this familiar face, smirked.

"Hello to you too, Gumo," said Len as he lightly punched the green-haired boy's shoulder. "Feel like going for another round?"

"No, thank you. I'm spent. I honestly never knew that Lexaeus was all that hard." Gumo shook his head and laughed as he and Len walked away from the portals.

"In your defense, he is pretty hard to beat. Still, as the next Guardian, you should be prepared for anything," Len reminded him.

Gumo rolled his eyes. Once Xehanort had been defeated by Sora and his friends for good, the remaining Keyblade Masters, namely, Yen Sid, King Mickey, Aqua and Riku, had decided that they would spread the power of the Keyblade to the rest of the worlds in order to ensure that others would be well-prepared on the off-chance that the Heartless came back. Over the years, Keyblade wielders travelled to the many other Worlds, ridding them of Heartless and locking their Keyholes. Over time, peace was restored throughout the Worlds, and the Heartless ceased to be, as the Darkness was kept well under control. Subsequently, the Nobodies disappeared, as did the Dream Eaters, seeing as there were no more Sleeping Worlds.

At some point in time, Yen Sid suggested that Keyblade Masters be spread out across the Worlds as a countermeasure. As per the laws, they would avoid meddling in the affairs of the other Worlds. Eventually, almost all known Worlds had a resident Keyblade Master, known as a Guardian. Guardians were tasked with ensuring the safety of their Worlds from anything that posed a threat, including other Keyblade Wielders, essentially preventing history from repeating itself. Even so, Guardians were still Masters. Therefore, they were still allowed to train others in the art of the Keyblade, alongside conducting the Mark of Mastery exam. They were also tasked with either appointing and training a successor, or naming an heir. In Gumo's case, it was the latter.

"Don't forget you're in line to be a Guardian as well," Gumo pointed out. Len shook his head. "Rin's already in charge of her own World, and I don't plan on taking your place as next-in-line for Destiny Islands." Gumo laughed, earning him a quizzical look from Len. Noting the confusion on his face, he explained.

"I wasn't talking about either of those. You're already a Master, Len. Why not go do a little sightseeing? You can find a World you like, settle down and all," he suggested.

"I'm only seventeen, Gumo. Keyblade Master or not, I have plenty of years left to live. There's no rush for me. And besides, I'm not even all that skilled," reasoned Len.

Gumo rolled his eyes again, mostly in annoyance this time. "Sure. The youngest boy to ever become Master since Riku isn't all that skilled. Just admit it, Len; you're in love with my sister, aren't you?" Gumo smirked as the blonde flushed slightly.

"What gave you that idea?" Len laughed nervously, but Gumo waved him off. The mere look on his face had given him away.

"Forget it, let's just get back home," he muttered, more to himself than anything. Len opened his mouth as he tried to explain himself, but gave up, and fell into step beside his friend, knowing full well that Gumo wouldn't listen to him.

He scoffed as the feeling of exhaustion rose within him; knowing Gumo, so was he.

* * *

The creature moved, its beady yellow eyes taking note of its surroundings. How it came to be, it did not know, nor did it care. There was only one goal, and that was to cure its hunger.

_Hearts,_ it thought. _Need. Hearts. _The creature surfaced momentarily, scratching its head, as if it would silence the voice in his head. Frustrated, it dropped into the ground once more, travelling along the stone pathways, paying no heed to its surroundings. What mattered most were the Hearts.

Had it been given the luxury of time, though, it might have noticed the floating columns. Light shone through the cracks in the rocks, and had it been any stronger, the creature, along with most of its kind, would probably have perished far too long ago.

_But, then again, this _is _the Realm of Darkness. Why should there be anything to harm the denizens of the night? Least of all in their own birthplace._

The man smiled. The creature surfaced once more, glancing in the man's direction. It could feel it; the instinct within itself. Somehow, it simply knew when there were Hearts around. But another look in the being's direction, and within him, a thought rose.

_Move._

It was a simple enough command, nothing more than a word. But the creature… Though it was dubbed a Heartless, it could still feel, and what it felt from the man was nothing more than power. Indeed, the creature did as bid, and so it sunk, seeping across the ground at a pace faster than before.

The man stood quietly. At the very least, his command over the power of Darkness had not diminished over the past few months. His command of the Keyblade, however, remained questionable, at best. But that would be a problem for another day. Perhaps when the Darkness failed him, if such a day would ever come to be.

Turning his attention back to the Heartless, he thought to himself. _It knows nothing of its existence. Nothing. Ironic, that a creature of Darkness would also be one of Nothingness._ He chuckled, but stopped. He could sense it; another Heart tainted by Darkness. He turned then, a friendly sight greeting his eyes.

"Are the preparations complete?"

"Ready as they've ever been."

He looked at his companion curiously. "Strange. Just yesterday, it was said that they would not be ready for another week."

The boy shook his head. "The readings were off the charts today. A spike, if you will."

"Hm." He nodded at the explanation. "Impressive, Mikuo, though I suppose I should expect no less from you of all people."

Mikuo's eyes narrowed. "You can drop the act, Kaito. It's not as if Meiko's around right now." His response earned nothing but a laugh from Kaito, and he did his best to suppress a growl, lest he enrage the blue-haired man.

"Patience, patience. Wait until we bring her back. Then, you can… _Try_ to kill me." He snickered, as if he'd recited the line a thousand times over, before looking back at the boy, a serious gleam to his eyes. "Tell Meiko to ready up; we leave by nightfall."

Mikuo nodded wordlessly, and left the room to run his errand. Kaito turned. The Shadow from earlier was now lost in a sea of Heartless. Drove upon drove slithered along the network of pathways, scurrying towards the portal that awaited them at the end of each path.

Forming a portal of his own, he pulled up the hood of his cloak. _I will bring you back,_ he thought as he stepped through._ No matter the cost, no matter the sacrifice, I will see that it is done._

* * *

Len opened his eyes. A quick glance at the clock told him he still had plenty of time for sleep. He stared out at the night sky from his bedroom window.

_Still filled with Stars, _he reassured himself, sighing in relief. Lying back down, he thought back on the day's events. Yes, it had been a busy day, but it was as normal a day as he was going to get. At least, it had been, up until Gumo questioned him again on their trip back.

_You're in love with my sister, aren't you?_

An arm across his face, he groaned. Contrary to popular belief, Keyblade Masters were allowed to have relationships, to have families, just as much as anyone else was. However, it was discouraged as Masters, particularly Guardians, required strong hearts to carry out their duties. Relationships were more than likely to be used against them as a weapon, thus weakening them in times of need.

_So what if I like her? That's not what matters here. The fact is she doesn't see me that way. _It was a simple thought, albeit a pessimistic one. One that he'd told himself countless times before.

As he dragged his feet out of bed, Gumo's words played again in his mind.

_What if she does like you? What then, Len?_

He shuffled over to the kitchen, feeling thirsty all of a sudden.

_That's about as likely as a Heartless turning human again._

He retrieved the orange juice in the fridge, pouring himself a glassful.

_Sora turned into one, but Kairi saved him, remember?_

Gulping down the juice in one go, he turned on the tap as he began washing the glass.

_You two grew up together. Even if I am her brother, there are some things about her I just don't know. But I do know this. She likes you, Len. Whether you believe me or not is up to you, though._

Placing the glass on the rack, he slumped against the fridge, the warmth it emanated flowing into him. He pulled his knees close, and rested his head on them. It was a habit he'd picked up from his childhood days. The world he lived in had been so simple. Just him, Gumi, Rin, and Gumo growing up together, having new adventures every day. How he missed those days, those simpler times.

His reminiscent thoughts were interrupted as he looked up. Something was off. Certainly, he'd felt fear many times before, from the time he nearly drowned to when Gumo saved him from a rogue Heartless. But nothing could compare to this… This sensation.

He exited his house, searching for the source of his unease. He scanned his surroundings, but nothing seemed to catch his eye. The Paopu trees swayed gently in the wind, their fruits noticeable even in the darkness of the night. Sensing nothing nearby, he proceeded to walk along the beach. Countless waves crashed onshore as they'd done for all eternity, and within a few minutes, he'd combed the entirety of the small island he called home.

_Everything seems normal enough. So why do I get the feeling that we're in danger? _Len frowned. There was only one place left to check.

* * *

Even for a World, the Destiny Islands was a relatively small one. It comprised of the main islands along with its surrounding islands, several of which served as homes for its many residents. The rest of the World was basically ocean, ocean and even more ocean.

_But this island is special, _Len thought as he walked over to the waterfall, the loud splashes drowning out all other noises. Hardly anyone knew, but the waterfall, or at least what lay beyond it, was the path to freedom, the World's Heart. Sealed behind a locked door, it was thought to have disappeared after Sora restored this World centuries ago.

_Yet, here it is. They even managed to connect this Keyhole to Radiant Garden, along with all the others,_ he thought to himself. Somehow or other, the Guardians had discovered that they could use the Keyholes as a mode of transportation between the Worlds, as long as the Keyhole had been sealed before. A much more efficient way to travel, as opposed to using the Corridors of Darkness, which threatened to devour one's Heart, or even the Gummi ships, as most, if not all, of the Worlds had had their barriers restored.

Slowly inserting his Keyblade, he turned it, unlocking the door. Stepping inside, he quickly shut the door behind him; friends they may be, but Gumo was still Guardian. It was more than likely that he would be held responsible if anything were to go wrong with the Heart of the World, regardless of who the true culprit was.

_That sensation I felt… It was a Heartless, no doubt about it. But they're like loose change around the house; where there's one, there's always more. _The very thought of his home being threatened once more by those damned creatures was enough to scare him. Yet, as he looked around, he could see very clearly for himself: there was nothing here. The Heart was intact, just as it had been for so long.

As he walked around the chamber, something caught his eye. Turning quickly, his gaze narrowed as he stared at the pools of black liquid which formed opposite him. From them came several creatures, all of them jet-black with beady yellow eyes, the only difference being their sizes. A few of them were as large as Len was, but he knew for sure they were nowhere near as strong as he was. The thought comforted him, and a smirk formed on his lips as he readied his weapon.

The Shadows, growing restless in the presence of such a powerful Heart, crawled over to the young Master as the stronger Neoshadows sunk into the ground. His training had prepared him for this, though, and he unleashed a light Fire spell, cloaking himself with balls of flame that scorched the Shadows. They disappeared, leaving behind wisps of black smoke.

He turned his attention to the Neoshadows as, one by one, they surfaced. Unlike the Shadows, they were more organized, and their attacks, although mostly an annoyance, were deadly nonetheless. Keeping his Keyblade close, he watched as the five of them circled him. One of them lunged backwards, before abruptly spinning forward with its claws poised to strike. Len raised his sword, parrying the attack and stunning the Neoshadow in the process. Bringing it back down, he sliced it in half, and it dispersed in the exact same way the Shadows did.

Two more came at him, and he repeated the process of parrying and attacking before sending one of them flying into the remaining three, effectively dispatching them in one go. He inhaled deeply; he hadn't been forced to defeat Heartless for a while, and he'd forgotten how exhausting the entire process was.

"I'd better go find Gumo. He needs to know what's going on," Len muttered as he dismissed his Keyblade. No sooner had he uttered those words than a voice spoke from behind him.

"You needn't find him. After all, he's right here with us."

Len turned and found nothing but the purple-black tone of a Corridor of Darkness. But that wasn't what caused him to feel terror; no, it was what lay within the Corridor. Sprawled on the ground was none other than Gumo, and Len could only watch in horror as another portal opened up underneath the unconscious boy, swallowing him whole and sending him off to parts unknown.

The Corridor closed, revealing a hooded man standing behind it. Len, who did his best to control his anger, asked softly, "Where did you send him?"

"Nobody knows. Only the light in his heart can guide him," the man snickered. His voice was deep, but the way he laughed only made him sound more maniacal. Unable to hold back, the blonde grabbed the man's wrist and pulled him close.

"Bring. Him. Back." Through gritted teeth, he forced out the words, but the man merely shook himself free. Snapping his fingers, he opened yet another Corridor. This time, though, it was Gumi who stood within it, fear and confusion etched onto her face. Len froze at the sight, and the man snapped his fingers again, closing the portal.

"Now, what do you think I'll do to her, hmm?" Although his face was barely visible, Len could tell the man was smiling.

"Don't you touch her. I swear I'll kill you," he snapped.

"Touched a nerve, did I?" The man threw his head back and laughed again. Extending his arm, he summoned his weapon. Len blinked. Like him, this madman was a Keyblade Wielder.

Summoning his own weapon, Len assumed a fighting stance as his mind started preparing strategies to use against this mysterious figure. Lifting his left hand, a ball of Darkness formed, and he aimed for Len. As the shot released, Len dodged, sending a thick chunk of ice towards the man. As soon as it came into contact with the man's cloak though, it shattered, leaving several shards on the ground.

The man smiled, as if he could read Len's thoughts. "You're probably thinking that I've got horrible aim, seeing as a small shot like that could miss you." Len narrowed his gaze, and the man continued. "Well, let's just say that it wasn't meant for you."

It took a moment for the words to sink in, and Len realized that he wasn't the man's target. Turning, he saw that the Heart had turned much darker than it should have been. The Keyhole flung open, and Darkness poured out of the Heart. He realized then that right from the very start, all this man had wanted were the Islands.

The man pulled back his hood, letting his spikey blue hair show, a satisfied smile on his face. He snapped his fingers, opening portals beneath both his feet and Len's, but Len made no effort to escape. His home was lost, his friends were gone. Silently cursing himself, his eyes met those of his foe, and his voice rang out in his head, as if by telepathy.

_Defeat the Heartless. Perhaps, then, you may yet see your friends alive._

The voice laughed darkly, and Len could imagine the man throwing his head back in the same insane manner from earlier. Closing his eyes, he let the tears stream down his face as the portal closed above him. But even behind those eyelids, he knew for sure what surrounded him.

Darkness. It was all there was.


End file.
